Sydney, Dec 01: Spider monkeys in Mexico have been found chewing fragrant plants and then smearing the chewed mash all over their body in a 'routine' fashion, which has been dubbed by a group of scientists as a "self-anointing" fragrant ritual.
And though the purpose behind such 'anointing' ritual still remains unknown, researchers believe that it may possibly be for signalling of social status or to increase sexual attractiveness
A recent paper published in the journal 'Primates' revealed that male Mexican spider monkeys chew the leaves of mainly three aromatic plants: the Alamos pea tree, a flowering trumpet tree, and wild celery.
Matthias Laska, a professor of zoology at Linköping University in Sweden, who carried out the research, told Discovery News that the monkeys always applied just one plant species at a time, and the application was a routine affair lasting between 30 seconds to two minutes.
"In the majority of cases, the arm that did not hold the scent-bearing material was held high or grabbed a branch above the animal," ABC Online quoted Laska as writing in his report.
The researchers observed the 'self anointing' behaviour 20 times in two male spider monkeys that were part of a free-ranging group at the Parque de Flora y Fauna Silvestre Tropical in Veracruz, Mexico.
This is not the first time that monkeys have shown such behaviour. Similar routines have been spotted among capuchin monkeys, owl monkeys, other spider monkeys and lemurs.
However, in most of these cases, the scientists speculate that the leaf mash might have been used to mitigate topical skin infections or repel bugs.
This is the first time that Laska and his team has observed that most of the plants chewed by the monkey spiders had 'fragrant' values rather than medicinal use.
"Only wild celery is known to have insect-repelling compounds and anti-fungal properties. The other plants simply smell good," the report said.
The scientists, therefore, conclude that self-anointing "may play a role in the context of social communication, possibly for signalling of social status or to increase sexual attractiveness", much akin to the use of cologne by man.
While the chemistry behind this remains a mystery, the odours may mimic fragrances of the naturally occurring primate steroids, presumed to act as sex-stimulating pheromones.
But not all monkeys want to smell like flowers and celery. Some have been observed applying citrus and tobacco leaf mashes to their bodies, as reported by Dr Mary Baker, Assistant Professor of Anthropology at Rhode Island College.
There are other scientists, who are of the belief that there could be other possible reasons for this behaviour.
"I also wonder whether it may function to stimulate or clean the gland that they rub the plant mixture on," ABC quotes Dr Christina Campbell, a scientist at the Cotsen Institute of Archaeology at the University of California at Los Angeles, as saying.
Bureau Report